Help! Bad dog has me losing my mind.

Has anyone else's dog started acting out since they've been pregnant? I'm almost 15 weeks now and my 3 years old dog (German Shorthaired Pointer) has been completely ignoring any commands I give her. She's always been a really good dog, but suddenly she doesn't follow even the simplest commands for me (Sit, stay, load up, kennel). She's always been so obedient and listened so well and now she does the exact opposite of what I say. I had to lift her up in my jeep last night and she's always been fine in the very back, but she kept jumping into my backseat so we had to redo it 4 times until I gave up, mind you she's 45 lbs. Today, I asked her to stay while I put shoes on to take her out and she ran. The other day I told her to get in her kennel before I had to leave the house (she's never in there longer than 1-2 hours) and she refused. I had to force her in there and cut my arm from squishing it in between her and the door she was so insistent on getting out. I'm really starting to feel stressed about this because my patience is wearing so thin that I'm feeling like all I'm doing is yelling at her lately and being mean to her. It's really important to me that she doesn't feel like things have completely changed because a baby is coming, and if this behavior continues when baby gets here I'm worried my patience will be so thin I'll start to hate her. Please help!!